Module 2 Biological Effects
1. Biological effects begin with the ionization of atoms
EO3 State the method by
a. The method by which radiation causes damage to human
which radiation causes
cells is by ionization of atoms in the cells. Atoms make
damage to cells.
up the cells that make up the tissues of the body. Any
potential radiation damage begins with damage to atoms.
Review the four types of
b. A cell is made up of two principal parts, the body of the
cell and the nucleus. The nucleus is like the brain of the
c. When ionizing radiation hits a cell, it may strike a vital
part of the cell like the nucleus or a less vital part of the
cell, like the cytoplasm.
Some cells are more sensitive than others to
environmental factors such as viruses, toxins, and
a. Actively dividing and non-specialized cells
1) Cells in our bodies that are actively dividing are more
sensitive to ionizing radiation.
2) Cells that are rapidly dividing include blood-forming
cells, the cells that line our intestinal tract, hair follicles,
and cells that form sperm.
b. Less actively dividing and more specialized cells
Cells that divide at a slower rate or are more specialized
(such as brain cells or muscle cells) are not as sensitive
to damage by ionizing radiation.
Possible effects of radiation on cells
Several things can happen when a cell is exposed to
EO4 Identify the possible
ionizing radiation. The following are possible effects of
effects of radiation on cells.
radiation on cells.
a. There is no damage
Cells repair the damage and operate normally